Ecologists recently introduced a species of native predatory beetles into an agricultural valley to reduce the population of crop-damaging aphids. Over the following six months, aphid populations decreased dramatically across farms throughout the valley. The ecologists concluded that the introduction of the predatory beetles was the primary cause of the reduction in aphid populations.
Which of the following statements, if true, provide support for the ecologists' conclusion?
- In neighboring valleys with identical weather patterns where the predatory beetles were not introduced, aphid populations remained unchanged during the same six-month period.Cevap
- BAphid populations in the valley experienced an outbreak of a fatal fungal disease during the same six-month period.
- Field observations confirmed that the introduced beetles consumed large quantities of aphids and successfully established breeding populations on the valley's farms.Cevap
- DFarmers in the valley had previously tried synthetic chemical sprays that failed to control aphid populations.
- EThe total crop yields in the valley increased significantly following the release of the predatory beetles.
Cevap
The statements establishing that aphid populations remained unchanged in nearby control valleys and verifying that the introduced beetles actively preyed on aphids both strengthen the argument.
The conclusion asserts that introducing predatory beetles caused the aphid decline. The statement regarding neighboring valleys serves as a control group, showing that without beetles, aphid populations did not decline under identical weather conditions. The statement regarding field observations confirms the direct physical mechanism of predation. Both statements logically increase the likelihood that the beetles caused the decline.
Adım Adım Çözüm
Anahtar Kavram
Strengthening Arguments by Ruling Out Alternative Causes and Validating Causal Mechanisms